An entertaining but uneven Carmina Burana at Tanglewood

Carl Orff’s Carmina Burana works best when approached with a healthy dose of irreverence. Although the cantata considers some weighty philosophical subjects – the caprices of faith, the vagaries of love and the general way of all flesh among them – Orff stacked the score with bawdy melodies that underscore the humorous and venal nature of the Medieval source poems. Fortune’s wheel turned hither and yon in the Boston Symphony Orchestra’s performance of the work at Tanglewood, but at its best, music director Andris Nelsons channeled a welcome immediacy and hard-driving forward momentum that made for some thrilling passages. Among the major American orchestras, the BSO has perhaps the most charged soundscape, and the dashes of roughness one heard especially in the early movements set the tone for a wild ride down the garden path to Hell.

The most important elements of Orff’s orchestration could hardly be improved. The percussion section handled their battery of assignments with humor and skill, yet without overselling the various appearances of potentially kitschy instruments like the cog rattle, sleigh bells or castanets. The doubled pianos and celesta brought an appropriately eerie otherworldliness whenever they appeared. Especially when strumming or playing pizzicato, the strings approximated a rustic verisimilitude that particularly suited the In Taberna sequence. Occasionally, Nelsons’ focus turned a bit too cerebral – the bassoon solo that opens Olim lacus colueram sounded ponderous, the Blanzifor et Helena sequence lacked a crashing energy – but on a whole, he and the BSO delivered a supremely entertaining reading of the score.

The Tanglewood Festival Chorus sounded best at forte, as in O fortuna and In taberna quando sumus. Small choirs suffered from balance issues and unsteadiness of pitch, particularly in the higher female voices. Members of the Boston Children’s Chorus sang sweetly in the Cour d’amours section. As usual, Erin Morley showed herself a scrupulous musician in the soprano solos – her trill could make the birds that wing around the Tanglewood campus green with envy – but her vocal characterization lacked the lustiness to convince as a young girl on the brink of first love. Reginald Mobley’s countertenor sounded hollow and artificially produced in Olim lacus colueram, and the aria loses much of its dark comedy without the threat of strain you hear in a tenor voice. In the most substantial vocal assignment, baritone Will Liverman sang with a compelling tone that sometimes wanted for expressiveness. At its most bombastic, the orchestra often covered him.

The concert opened with a perfunctory performance of Beethoven’s Leonore Overture no. 3, lacking much in the way of insight or expressiveness. Nelsons favored briskness over detail, and the condensed narrative of Fidelio that emerges across the piece, the triumph of morality over the darkness of evil, remained murkily unexplored.